Function keys

On your wonderful wired or wireless Apple keyboard, there are a number of function keys, F1 to F12 which have a second function, for most of them. F1 = lower brightness, F2 = higher brightness, F3 = exposé, F4 = dashboard, F7 = previous tune, F8= Play/Pause, F9 = next tune, F10 sound off, F11 = lower volume, F12 = higher volume.

By default, the active function is the function represented by the pictogram, so pressing F12 will actually increase the volume of sound. However, some of these functions, dependent on the running application may have another action.  Example F11 also reveals the desktop, by moving all open windows out of the screen. In order to actually use these secondary function, you must press the fn key together with the F key. So fn + F11 actually reveals the desktop. fn + F10 exposes all the windows of the current application.